Fire hydrants are usually connected to a municipal (drinking) water system for the purpose of extinguishing fires, and dispensing water for other purposes, such as construction or for human consumption and use during appropriate situations. Fire hydrants commonly are one of two types: wet-barrel fire hydrants and dry-barrel fire hydrants. A wet-barrel fire hydrant is a fire hydrant in which pressurized water remains in the hydrant body at all times because the control valve is commonly situated near the top of the barrel. The control valve of a wet-barrel fire hydrant is commonly a plug which translates horizontally to close or open an individual nozzle of the fire hydrant. A dry-barrel fire hydrant is a fire hydrant in which the upper and lower barrels, or any vertical barrel or standpipe from the hydrant body to the hydrant shoe, of the hydrant are “dry” and thereby devoid of water. The placement of the control valve of a dry-barrel hydrant is typically located underground near the connection of the standpipe to the hydrant shoe and is often controlled by a stem connected to the bonnet. The control valve is typically mounted on, adjacent to, or within the hydrant shoe. Opening the control valve allows pressurized water to rush into the upper barrel of the hydrant. Upon closing the control valve, the water drains from the upper and lower barrels to render the upper and lower barrels “dry” again. However, existing fire hydrants are designed such that any individual can open a hydrant cap with simple tools and deposit contaminants or other hazardous materials into the hydrant. A contaminant may be a foreign, unnatural, or undesirable substance. A contaminant may also include an unnatural or undesirable amount of naturally occurring or desired substances. Replacing the hydrant cap seals the hydrant, and then opening the gate valve, again with simple tools, allows for water to mix with the contaminants and spread within the water supply.
A conventional dry-barrel fire hydrant is illustrated in FIG. 1. The fire hydrant 100 includes a barrel 105, which can include both an upper barrel 110 and a lower barrel 120. The fire hydrant 100 can be in communication with a hydrant shoe 130, which is preferably in fluid communication with a water supply 150.
The lower barrel 120, which is commonly referred to as a stand pipe, is connected to the hydrant shoe 130, which is commonly referred to as an elbow, at its lower end 107. The upper end 106 of the lower barrel 120 is connected to the upper barrel 110, which is commonly referred to as a hydrant barrel. The upper barrel 110 is preferably above-ground, making it accessible and easily discoverable for users. To be released from the hydrant, water can flow from the water supply through the hydrant shoe, the barrel, and then outwardly from a nozzle.
The upper barrel 110 includes a nozzle assembly 140, an operating mechanism 160, and a bonnet 170. The nozzle assembly 140 is adapted to allow water to flow out of the hydrant 100. The nozzle assembly 140 includes a nozzle outlet 142, which extends laterally from the upper barrel 110, and a nozzle cap 146. The nozzle outlet 142 can include a nozzle threading 144 and a nozzle opening 148. The nozzle cap 146 is removeable from the nozzle outlet 142 via the nozzle threading 144, enabling the nozzle cap 146 to be attached and removed from the nozzle outlet 142, as needed. If water rises through the upper barrel 110 of the hydrant 100, the water can escape the hydrant 100 via the nozzle opening 148, if the nozzle cap 146 is removed from the nozzle outlet 142.
The operating mechanism 160, which often comprises an operating nut 162, is rotatable, such that a valve assembly 180 can be adjusted to control water flow through the hydrant 100 from the water supply source 150. In many preferred embodiments, the operating nut 162 has a pentagon shape, which may be the same shape as a nut 147 of the nozzle cap 146. By having the same shape, a single tool can be used for both to remove the nozzle cap 146 from the nozzle outlet 142, and for rotating the operating nut 162 to control the valve assembly 180. Although, the pentagon-shape is considered “non-standard” and requires a special wrench, it may also be easily operated with different tools, such as a pipe wrench. This shape can also reduce unauthorized access to an inner cavity of the hydrant 100.
At the lower end of the lower barrel 120 is the valve assembly 180. The valve assembly 180 includes a valve seat 182, a hydrant valve 184, and upper plate 186 and lower plate 188. The valve assembly 180 is adapted to control the water flow through the hydrant 100, for example, to a fire hose connected to the nozzle outlet 142.
An operating stem 190 extends from the valve assembly 180 to the operating nut 162. The operating nut 162 controls the operating stem 190 to open/close the valve assembly 180, as desired or necessary. As the operating nut 162 is rotated, the hydrant valve 184 of the valve assembly 180 can be opened or closed, depending on the direction of the rotation.
As described, the lower end 107 of the lower barrel 120 is in communication with the valve assembly 180. The lower end 107 of the lower barrel 120 is also in communication with the hydrant shoe 130 via a flange 132. The hydrant shoe 130 is connected to the water supply 150.
Because of the sheer number of fire hydrants in service, it is not cost effective to replace all existing hydrants with another design. Rather, an anchor valve is needed that can be retrofitted to existing hydrants and that is also tamper-resistant itself. By locating the anchor valve underground, adjacent to the hydrant, the ability of an evildoer to quickly and stealthily attempt to introduce contaminants to the water supply is greatly reduced.
As it is not practical or possible to monitor every one of millions of fire hydrants currently in service, an anchor valve is needed that prevents contamination such as described above, yet is simple in operation, and once installed does not require maintenance or cause any complication when using the hydrant for its proper purposes. If an evildoer does open the hydrant cap after the anchor valve is installed, any contaminants will be contained within the hydrant and flushed out of the system once the valve is opened.
Fluid delivery systems also use hydrants or other valves to release fluids for various applications. For example, fuel is delivered in pipe systems and is accessed for usage at a number of release valves. In the case of an airport, fuel may be distributed under the runways and gate areas for easy dispensing to waiting aircraft, eliminating the need for mobile fuel trucks. It is desirable to prevent any contamination which may occur during a fueling operation from spreading into the main fuel supply system, thus another application of the present invention.
Fluids also need control and contamination prevention in appliances, for example. In the case of a dish or clothes washer, it is desirable to prevent contaminated or “grey” water from backing up into the water supply system. In the case of a lawn sprinkler system, preventing water backing up into the water supply system is also desirable, as sprinkler systems may come into contact with fertilizers and pesticides which are not fit for human consumption. These use of the anchor valve of the present invention to prevent such contamination is yet another use.
It is most desirable to locate the anchor valve of the present invention close to the dispensing point, for example, a hydrant, to minimize the volume of fluid possibly contaminated. However, the valve of the present invention may be located at any point in a fluid system, as required or determined by design constraints.
A number of devices are used for joining sections of pipe. For example, U.S. Pat. No. 7,004,511 discloses a coupling device with a sealing ring. U.S. Pat. No. 4,569,542 discloses a bolt type coupling designed to provide clearance functions, so that gasket compression is achieved before the gripper ring effectively grips the pipe and locks the coupling in place when the bolt fasteners are tightened. U.S. Pat. No. 5,803,513 discloses the use of a plurality of skid pads strategically placed over the teeth of the gripping ring to prevent it from prematurely engaging the pipe before the compression of the accompanying gasket. U.S. Pat. No. 6,691,732 discloses a hydrant security device that is installed on top of a fire hydrant to prevent decontamination. However, none of these devices functions to join sections of pipe while incorporating an anchor check valve, which also protects the supply system from contamination.
The check valve is the heart of the anchor valve. A flapper valve is used in one embodiment which is durable yet uncomplicated, requiring no maintenance and is unaffected by cold, enabling the anchor valve to be buried underground. Traditionally, mechanical swing-type check valves have been used, but these check valves are complicated and prone to mechanical failure, which is undesirable especially in the case of a fire hydrant, whose principal use is in an emergency situation.
What is needed is an anchor valve that secures a fluid system from contamination with a check valve that does not impact operation but also is tamper-resistant and is easily retrofitted to existing as well as new hydrants at time of installation.